Battery monomer, battery device and electric equipment

Abstract

The embodiment of the utility model provides a battery monomer, a battery device and electric equipment, the battery monomer comprises a shell, an electrode unit and a protection assembly, and an accommodating space is formed in the shell. The electrode unit comprises at least one electrode assembly, and the electrode assembly is arranged in the containing space. The protection assembly is arranged in the accommodating space, is positioned between the electrode unit and the shell, and is configured to be started when the battery monomers are subjected to thermal runaway so as to inhibit the thermal runaway. The protection assembly comprises at least one protection unit, the protection unit comprises a packaging structure and a safener sealed in the packaging structure, the protection unit is configured to enable the packaging structure to be melted to release the safener when thermal runaway happens to the single battery, and the safener is used for inhibiting thermal runaway. The reliability of the battery device can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of batteries, and more specifically, to a battery cell, a battery device, and an electrical device. Background Art

[0002] Battery cells are widely used in electronic devices, such as mobile phones, laptop computers, battery cars, electric vehicles, electric airplanes, electric ships, electric toy cars, electric toy ships, electric toy airplanes, and electric tools, etc.

[0003] In the development of battery technology, how to improve the reliability of battery devices is a research direction in battery technology. Summary of the Utility Model

[0004] The present application provides a battery cell, a battery device, and an electrical device, which can improve the reliability of the battery device.

[0005] An embodiment of the present application provides a battery cell. The battery cell includes a housing, an electrode unit, and a protection component. An accommodation space is formed inside the housing. The electrode unit includes at least one electrode assembly, and the electrode assembly is disposed in the accommodation space. The protection component is disposed in the accommodation space and is located between the electrode unit and the housing. The protection component includes at least one protection unit. The protection unit includes a packaging structure and a safety agent sealed in the packaging structure. The protection unit is configured such that when a thermal runaway occurs in the battery cell, the packaging structure is melted to release the safety agent, and the safety agent is used to inhibit the thermal runaway. A tab is provided at the top end and / or the bottom end of the electrode unit. The protection component covers at least a part of the outer peripheral side of the portion between the top end and the bottom end of the electrode unit, and is configured to release the safety agent to the portion between the top end and the bottom end of the electrode unit.

[0006] The battery cell of this embodiment is provided with a protection component inside the outer shell. The protection component is located between the outer shell and the electrode unit. When the battery cell undergoes thermal runaway, the protection component is activated to suppress thermal runaway, slow down the further spread of combustion, reduce the risk of a large number of battery cells experiencing thermal runaway caused by the rapid spread of the thermally runaway battery cell to other battery cells, and improve the reliability of the battery device. Further, when the battery cell undergoes thermal runaway, the encapsulation structure of the protection component is melted to form an opening, and the safety agent inside is released to suppress thermal runaway, which can play a fire extinguishing role inside the battery cell, thereby slowing down the further spread of combustion, reducing the risk of a large number of battery cells experiencing thermal runaway caused by the rapid spread of the thermally runaway battery cell to other battery cells, and improving the reliability of the battery device. Moreover, by selecting an encapsulation structure with better chemical stability, the encapsulation structure is not easily reactive with the electrolyte, so that the safety agent does not come into contact with the electrolyte during normal use, reducing the impact on the electrolyte, and there are also more choices for the safety agent. Further, the protection component is arranged between the side surface of the electrode unit and the outer shell, and is not easily interfered with by other components. Moreover, by setting the size of the outer shell, a relatively large installation space can be provided for the protection unit.

[0007] In some embodiments, the electrode unit includes a main body portion, a first tab and a second tab with opposite polarities. The main body portion includes a top surface, a bottom surface and a plurality of side surfaces. The plurality of side surfaces are connected between the top surface and the bottom surface. The first tab and the second tab are arranged on the top surface, and a protection unit is provided between the side surface and the outer shell.

[0008] In the above technical solution, the protection unit is arranged between the side surface and the outer shell. The side surface has a relatively high temperature when the battery cell undergoes thermal runaway, which can achieve a better fire extinguishing effect and is not easily interfered with by other components.

[0009] In some embodiments, the plurality of side surfaces include two first side surfaces with the largest area and arranged opposite to each other, and at least one protection unit is provided between at least one of the first side surfaces and the outer shell.

[0010] In the above technical solution, the area of the first side surface is the largest and its temperature is relatively high when thermal runaway occurs. Therefore, by arranging the protection unit between the first side surface and the outer shell, a better fire extinguishing effect can be achieved, and the protection unit can have a relatively large volume, improving the fire extinguishing ability.

[0011] In some embodiments, at least one protection unit is respectively provided between each side surface and the outer shell.

[0012] In the above technical solution, a protection unit is arranged between each side surface and the outer shell. Thus, when the battery cell undergoes thermal runaway, the protection component can play a fire extinguishing role for each side surface, further improving the fire extinguishing ability of the protection component.

[0013] In some embodiments, at least one protection unit is provided between at least two sides and the housing respectively, and a plurality of protection units provided between different sides and the housing are connected to each other.

[0014] In the above technical solution, the plurality of protection units connected together are not only convenient for assembly, but also can position each other, reducing displacement in the battery cell.

[0015] In some embodiments, at least one protection unit is provided between each side and the housing respectively, and all protection units located between all sides and the housing are connected to each other.

[0016] In the above technical solution, all the protection units connected together are not only convenient for the assembly of the battery cell, but also the protection component can extinguish fire on all sides.

[0017] In some embodiments, the plurality of sides include two first sides with the largest area and arranged opposite to each other, and the protection component further includes a connecting portion facing the bottom surface, and at least two protection units facing the two first sides are connected through the connecting portion.

[0018] In the above technical solution, a connecting portion is provided on the bottom surface to connect at least two protection units, so that the plurality of protection units and the connecting portion of the protection component are sleeved on the electrode unit, which is not only convenient for installation, but also hardly displaced, and plays an insulating role, insulating the electrode unit from the housing.

[0019] In some embodiments, the connecting portion includes a protection unit.

[0020] In the above technical solution, the connecting portion is arranged to include a protection unit. When the battery cell undergoes thermal runaway, the protection component can also extinguish fire on the bottom surface, improving the reliability of the protection component.

[0021] In some embodiments, one side of the opposite sides of the protection unit abuts against the electrode unit, and the other side abuts against the housing, and the encapsulation structure is an insulating structure.

[0022] In the above technical solution, the protection component directly insulates the electrode unit from the housing without setting other insulating parts.

[0023] In some embodiments, a protection unit is provided between the bottom surface and the housing.

[0024] In the above technical solution, a protection unit is provided between the bottom surface and the housing to form a fire extinguishing effect on the bottom surface when the battery cell gets out of control, improving the reliability of the protection component.

[0025] In some embodiments, the battery cell further includes an insulating film located in the accommodation space and sleeved on the outside of the electrode unit, and the protection component is provided between the insulating film and the electrode unit.

[0026] In the above technical solution, the protective component is arranged between the insulating film and the electrode unit. When thermal runaway occurs, the protective component can act on the electrode unit more quickly, thereby improving the response speed.

[0027] In some embodiments, the melting point of the package structure is T, and T satisfies: 130° C. < T ≤ 180° C.

[0028] In the above technical solution, the melting point of the packaging structure is set to be greater than 130°C to meet the temperature requirements of the battery cell during normal circulation. The melting point of the packaging structure is set to be less than or equal to 180°C so that it can melt in time to release the safety agent when the battery cell experiences thermal runaway.

[0029] In some embodiments, T satisfies: 140°C ≤ T ≤ 160°C.

[0030] The melting point of the packaging structure is set to be greater than 140°C to meet the temperature requirements of larger capacity battery cells during normal circulation. The melting point of the packaging structure is set to be less than or equal to 160°C to melt more quickly and release the safety agent when thermal runaway occurs in the battery cell.

[0031] In some embodiments, the packaging structure is a bag-like structure.

[0032] In the above technical solution, the packaging structure is set as a bag-like structure. Since the bag-like structure is thin, it is easy to be melted, and the bag-like structure is easy to deform, and can better adapt to the space inside the shell.

[0033] In some embodiments, the safener is a solid safener, a liquid safener, a gaseous fire extinguishing agent, or a safener that is both solid and liquid.

[0034] The safety agent can be set to multiple states to facilitate the selection of more suitable safety agents for different types of battery cells, thereby expanding the selection range of safety agents.

[0035] In a second aspect, an embodiment of the present application further provides a battery device comprising the above-mentioned battery cell.

[0036] In a third aspect, an embodiment of the present application further provides an electrical device, comprising the above-mentioned battery device, which is used to store or provide electrical energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the drawings without creative work.

[0038] Figure 1 Schematic structural diagram of a vehicle provided by some embodiments of the present application;

[0039] Figure 2 Schematic structural diagram of a battery device provided by some embodiments of the present application;

[0040] Figure 3 Exploded schematic structural diagram of a battery cell provided by some embodiments of the present application;

[0041] Figure 4 Another schematic structural diagram of a battery cell provided by some embodiments of the present application;

[0042] Figure 5 Schematic diagram of a protection component in an unfolded state in a battery cell provided by some embodiments of the present application.

[0043] Reference numerals in the specific embodiments are as follows:

[0044] 100, vehicle; 200, battery device; 300, controller; 400, motor; 500, battery cell; 600, box body;

[0045] 1, outer shell; 11, end cover; 12, housing;

[0046] 2, electrode unit; 21, main body portion; 211, top surface; 213, side surface; 214, first side surface; 22, first tab; 23, second tab;

[0047] 3, protection component; 31, protection unit; 311, encapsulation structure; 32, connection portion. Specific embodiments

[0048] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are some, but not all, of the embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the scope of protection of the present application.

[0049] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by those skilled in the technical field to which this application belongs; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above accompanying drawings are intended to cover non-exclusive inclusion. The terms "first", "second", etc. in the specification and claims of this application or the above accompanying drawings are used to distinguish different objects and not to describe a specific order or primary-secondary relationship.

[0050] Reference to "embodiment" in this application means that a specific feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of this application. The phrase appears in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments.

[0051] In the description of this application, it should be noted that unless otherwise clearly specified and limited, the terms "installed", "connected", "joined", "attached" shall be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0052] The term "and / or" in this application is merely a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this application generally represents an "or" relationship between the associated objects before and after.

[0053] In the embodiments of this application, the same reference numerals represent the same components, and for the sake of brevity, in different embodiments, the detailed description of the same components is omitted. It should be understood that the thickness, length, width, etc. of various components in the embodiments of this application shown in the accompanying drawings, as well as the overall thickness, length, width, etc. of the integrated device, are only illustrative and should not constitute any limitation to this application.

[0054] The term "plurality" as used in this application refers to two or more (including two).

[0055] In a battery device, if a battery cell undergoes thermal runaway and is not dealt with in a timely manner, it usually affects the remaining battery cells, resulting in a larger range of thermal runaway.

[0056] In view of this, the present application provides a battery cell. By arranging a protection component inside the outer shell, the protection component is located between the outer shell and the electrode unit. When the battery cell undergoes thermal runaway, the protection component is activated to suppress thermal runaway, thereby slowing down the further spread of combustion, being able to play a fire extinguishing role inside the battery cell, reducing the risk of a large number of battery cells experiencing thermal runaway caused by the rapid spread of the thermally runaway battery cell to other battery cells, and improving the reliability of the battery device.

[0057] The technical solutions described in the embodiments of the present application are applicable to various electrical equipment using battery cells and battery devices, such as mobile phones, portable devices, laptop computers, battery cars, electric toys, electric tools, vehicles, ships, and spacecrafts, etc. For example, spacecrafts include airplanes, rockets, space shuttles, and spaceships, etc.

[0058] For the convenience of description in the following embodiments, the electrical equipment is taken as an example of a vehicle for illustration.

[0059] Figure 1 It is a schematic structural diagram of a vehicle 100 provided in some embodiments of the present application.

[0060] As Figure 1 shown, a battery device 200 is arranged inside the vehicle 100. The battery device 200 can be arranged at the bottom, head, or tail of the vehicle 100. The battery device 200 can be used for power supply of the vehicle 100. For example, the battery device 200 can be used as the operating power source of the vehicle 100.

[0061] The vehicle 100 may further include a controller 300 and a motor 400. The controller 300 is used to control the battery device 200 to supply power to the motor 400. For example, it is used for the working power requirements during the start, navigation, and driving of the vehicle 100.

[0062] In some embodiments of the present application, the battery device 200 can not only be used as the operating power source of the vehicle 100, but also be used as the driving power source of the vehicle 100, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 100.

[0063] Figure 2 It is a schematic structural diagram of a battery device 200 provided in some embodiments of the present application;

[0064] As Figure 2 shown, the battery device 200 includes a box body 600 and battery cells 500. The battery cells 500 are accommodated in the box body 600. Among them, the box body 600 is used to provide an accommodation space for the battery cells 500, and the box body 600 can adopt various structures.

[0065] As an example, the housing 600 may include a first housing and a second housing. The first housing and the second housing are snapped together so that a closed space is formed inside the housing 600 to accommodate the battery cells 500. Here, "closed" means covered or closed, which can be sealed or non-sealed. The first housing can be a top cover or a bottom plate.

[0066] As an example, the housing 600 may include a top cover, a frame, and a bottom plate. The top cover and the bottom plate are respectively connected to the frame so that a closed space is formed inside the housing 600 to accommodate the battery cells 500.

[0067] In some embodiments, the housing 600 can be part of the chassis structure of the vehicle 100. For example, a part of the housing 600 can become at least a part of the floor of the vehicle 100, or a part of the housing 600 can become at least a part of the cross beams and longitudinal beams of the vehicle 100.

[0068] In some embodiments, the battery device 200 refers to an energy storage device, and the energy storage device includes a housing 600, and a door is provided on at least one side of the housing 600. The energy storage device includes an energy storage container, an energy storage cabinet, etc.

[0069] In the battery device 200, there can be multiple battery cells 500, and the multiple battery cells 500 can be connected in series, in parallel, or in a mixed connection. A mixed connection means that there are both series and parallel connections among the multiple battery cells 500. The multiple battery cells 500 can be directly connected in series, in parallel, or in a mixed connection together, and then the whole formed by the multiple battery cells 500 is accommodated in the housing 600; of course, the battery device 200 can also be that multiple battery cells 500 are first connected in series, in parallel, or in a mixed connection to form a battery module form, and then multiple battery modules are connected in series, in parallel, or in a mixed connection to form a whole and are accommodated in the housing 600. The battery device 200 can also include other structures. For example, the battery device 200 can also include a busbar component for realizing the electrical connection among the multiple battery cells 500.

[0070] Among them, the battery cell 500 can include a lithium-ion secondary battery cell, a lithium-ion primary battery cell, a lithium-sulfur battery cell, a sodium-lithium-ion battery cell, a sodium-ion battery cell, or a magnesium-ion battery cell, etc. The battery cell 500 can be in a cylindrical shape, a flat shape, a cuboid shape, or other shapes, etc.

[0071] Figure 3 Schematic diagram of the exploded structure of the battery cell provided in some embodiments of the present application; Figure 4 Another structural schematic diagram of the battery cell provided in some embodiments of the present application.

[0072] Such as Figure 3 and Figure 4As shown, the present application also provides a battery cell 500, which includes a housing 1, an electrode unit 2, and a protection component 3. An accommodation space is formed inside the housing 1. The electrode unit 2 includes at least one electrode assembly, and the electrode assembly is disposed in the accommodation space. The protection component 3 is disposed in the accommodation space and is located between the electrode unit 2 and the housing 1. The protection component 3 is configured to be activated when the battery cell 500 undergoes thermal runaway to suppress thermal runaway.

[0073] The housing 1 of this embodiment may include a housing body 12 and an end cap 11. The end cap 11 refers to a component that covers the opening of the housing body 12 to isolate the internal environment of the battery cell 500 from the external environment. Without limitation, the shape of the end cap 11 may be adapted to the shape of the housing body 12 to cooperate with the housing body 12. Optionally, the end cap 11 may be made of a material with a certain hardness and strength (such as aluminum alloy). In this way, the end cap 11 is not easily deformed when subjected to extrusion and collision, enabling the battery cell 500 to have higher structural strength. Functional components such as electrode terminals may be provided on the end cap 11. The electrode terminals can be used to electrically connect with the electrode assembly for outputting or inputting the electrical energy of the battery cell 500. In some embodiments, a pressure relief mechanism for releasing the internal pressure when the internal pressure or temperature of the battery cell 500 reaches a threshold may also be provided on the end cap 11. The material of the end cap 11 may also be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc. The embodiments of the present application do not make special limitations on this. In some embodiments, an insulating member may be further provided on the inner side of the end cap 11, and the insulating member can be used to isolate the electrical connection components in the housing body 12 from the end cap 11 to reduce the risk of short circuit. Exemplarily, the insulating member may be plastic, rubber, etc.

[0074] The housing body 12 is a component used to cooperate with the end cap 11 to form the internal environment of the battery cell 500. Among them, the formed internal environment can be used to accommodate the electrode assembly, electrolyte, and other components. The housing body 12 and the end cap 11 may be independent components. An opening may be provided on the housing body 12, and the end cap 11 is covered on the opening to form the internal environment of the battery cell 500. Without limitation, the end cap 11 and the housing body 12 may also be integrated. Specifically, the end cap 11 and the housing body 12 may first form a common connection surface before other components are put into the housing. When it is necessary to encapsulate the inside of the housing body 12, the end cap 11 is then covered on the housing body 12. The housing body 12 may have various shapes and sizes, such as cuboid, cylindrical, hexagonal prism, etc. Specifically, the shape of the housing body 12 may be determined according to the specific shape and size of the electrode assembly. The material of the housing body 12 may be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0075] The electrode assembly is a component in the battery cell 500 where an electrochemical reaction occurs. The housing 12 can contain one or more electrode assemblies. The electrode assembly is mainly formed by winding or laminating a positive electrode sheet and a negative electrode sheet, and a separator is usually provided between the positive electrode sheet and the negative electrode sheet. The portions of the positive electrode sheet and the negative electrode sheet having active materials constitute the main body of the electrode assembly, and the portions of the positive electrode sheet and the negative electrode sheet without active materials respectively constitute the electrode tabs. The positive electrode tab and the negative electrode tab can be located together at one end of the main body portion or respectively at both ends of the main body portion. During the charge and discharge process of the battery device 200, the positive electrode active material and the negative electrode active material react with the electrolyte, and the electrode tabs are connected to the electrode terminals to form a current loop.

[0076] The electrode unit 2 in this embodiment can include one electrode assembly or multiple electrode assemblies, and the multiple electrode assemblies are arranged in parallel.

[0077] The protection component 3 in the embodiment of the present application can be disposed between the top surface of the electrode unit 2 and the end cover 11. Exemplarily, the battery cell 500 includes a lower plastic between the end cover 11 and the electrode unit 2, and the protection component 3 is located between the lower plastic and the top surface of the electrode unit 2.

[0078] The protection component 3 in the embodiment of the present application is a material that does not react with the electrolyte under normal use conditions of the battery cell 500. The protection component 3 can be a solid-state phase change material. When the battery cell 500 undergoes thermal runaway, the solid-state phase change material changes to a liquid state to inhibit thermal runaway. Exemplarily, the solid-state phase change material can be pentaerythritol or neopentyl glycol, and pentaerythritol or neopentyl glycol can absorb heat through phase change when the battery cell 500 undergoes thermal runaway, thereby slowing down thermal runaway. Further, at least a part of its outer surface can be coated with an SiO2 layer.

[0079] In this embodiment, the battery cell 500 is provided with a protection component 3 inside the outer shell 1, and the protection component 3 is located between the outer shell 1 and the electrode unit 2. When the battery cell 500 undergoes thermal runaway, the protection component 3 is activated to inhibit thermal runaway, slow down the further spread of combustion, reduce the risk of a large number of battery cells 500 undergoing thermal runaway caused by the rapid spread of the thermally runaway battery cell 500 to other battery cells 500, and improve the reliability of the battery device 200.

[0080] In some embodiments, the protection component 3 includes at least one protection unit 31, and the protection unit 31 includes a packaging structure 311 and a safety agent sealed in the packaging structure 311. The protection unit 31 is configured such that when the battery cell 500 undergoes thermal runaway, the packaging structure 311 is melted to release the safety agent, and the safety agent is used to inhibit thermal runaway.

[0081] The protection component 3 of this embodiment may include one or more protection units 31. When multiple protection units 31 are included, the multiple protection units 31 may be connected together or independent of each other.

[0082] The protection unit 31 of this embodiment may be disposed between the top surface of the electrode unit 2 and the end cap 11. Exemplarily, the battery cell 500 includes a lower plastic between the end cap 11 and the electrode unit 2, and the protection unit 31 is located between the lower plastic and the top surface of the electrode unit 2.

[0083] A sealed cavity is formed inside the encapsulation structure 311 of this embodiment, and the safety agent is located inside the sealed cavity. The encapsulation structure 311 may be a soft bag-like structure or a box-like structure with a certain hardness, and a sealed cavity is formed inside the box-like structure.

[0084] Exemplarily, the material of the encapsulation structure 311 may be thermoplastic polyurethane (TPU), polyamide (such as PA12), polyvinylidene fluoride (PVDF), polyphenylene ether (PPO / PPE), modified polypropylene, etc.

[0085] The selection of the encapsulation structure 311 in this embodiment may be based on its melting point, and the range of the melting point may be determined according to the usage requirements of different types of battery cells 500.

[0086] The safety agent in this embodiment refers to a material that inhibits thermal runaway. For example, it inhibits thermal runaway by rapid heat absorption, chemical inhibition (interrupting the combustion chain reaction), releasing flame retardant gases, or forming a heat insulation layer, etc.

[0087] The safety agent in this embodiment may be gaseous, liquid or solid. Exemplarily, the gaseous safety agent may be carbon dioxide (CO2) or inert gas (such as a mixture of nitrogen + argon + CO2), etc. The liquid safety agent may be perfluorooctanone, silicone, modified water-based fire extinguishing agent added with fluoride and corrosion inhibitor, etc. The solid safety agent may be dry powder, ammonium dihydrogen phosphate (NH4H2PO4), carbonate, expanded graphite or S-type aerosol, etc.

[0088] The safety agent in this embodiment may also be composed of multiple materials, such as a composite safety agent composed of a fluorine-containing fire extinguishing main agent, a fluorine-containing flame retardant, a temperature reducer, and a corrosion inhibitor. Optionally, the safety agent is a composite safety agent formed by the combination of perfluorooctanone, perfluoropolyether, perfluorotriethylamine and potassium fluotitanate.

[0089] When thermal runaway occurs in the battery cell 500, the encapsulation structure 311 of the protection component 3 is melted to form an opening, and the safety agent therein is released to inhibit thermal runaway, which can play a role in extinguishing fire inside the battery cell 500, thereby slowing down the further spread of combustion and reducing the risk of thermal runaway of a large number of battery cells 500 caused by the rapid spread of the thermally runaway battery cell 500 to other battery cells 500, and improving the reliability of the battery device 200.

[0090] In some embodiments, the top end and / or the bottom end of the electrode unit 2 are / is provided with electrode tabs, and the protection component 3 covers at least a part of the outer peripheral side of the portion between the top end and the bottom end of the electrode unit 2 and is configured to release the safety agent to the portion between the top end and the bottom end of the electrode unit 2.

[0091] The electrode assembly of this embodiment can be cylindrical or other shapes.

[0092] The protection component 3 of this embodiment can cover all or part of the electrode unit 2 from the top end to the bottom end.

[0093] Optionally, the protection component 3 is arranged in a circle around the side surface of the electrode unit 2.

[0094] When thermal runaway occurs in the battery cell 500, the encapsulation structure 311 of the electrode unit 2 is melted, and the safety agent released therein plays a role in inhibiting thermal runaway on the side surface of the electrode unit 2.

[0095] With such an arrangement, the protection component 3 is arranged between the side surface of the electrode unit 2 and the housing, and it is not easy to interfere with other components.

[0096] In some embodiments, the electrode unit 2 includes a main body portion 21, a first electrode tab 22 and a second electrode tab 23 with opposite polarities. The main body portion 21 includes a top surface 211, a bottom surface and a plurality of side surfaces 213. The plurality of side surfaces 213 are connected between the top surface 211 and the bottom surface. The first electrode tab 22 and the second electrode tab 23 are arranged on the top surface 211, and a protection unit 31 is provided between the side surface 213 and the housing 1.

[0097] The first electrode tab 22 of this embodiment can be a positive electrode tab, and the second electrode tab 23 can be a negative electrode tab.

[0098] As Figure 3 and Figure 4 shown, the electrode unit 2 is formed by arranging a plurality of electrode assemblies. The electrode unit 2 includes two first side surfaces 214 and two other smaller side surfaces located between the two first side surfaces 214. The smaller side surfaces are formed by the curved surfaces of a plurality of electrode assemblies at the same position.

[0099] A protection unit 31 is provided between the side surface 213 of this embodiment and the housing 1. Among them, the entire protection unit 31 or a part of the protection unit 31 can be provided between one side surface 213 and the housing 1.

[0100] Optionally, at least one protection unit 31 is provided between the side surface 213 and the housing 1.

[0101] Exemplarily, one, two or more protection units 31 can be provided between one side surface 213 and the housing 1.

[0102] When at least one protection unit 31 is respectively provided between different side surfaces 213 and the housing 1, the number of protection units 31 provided between different side surfaces 213 and the housing 1 can be the same or different. The multiple protection units 31 between at least two side surfaces 213 and the housing 1 can be connected or not connected.

[0103] When the number of protection units 31 in this embodiment is multiple, the materials of the encapsulation structures 311 of the multiple protection units 31 can be the same or different. The materials of the safety agents of the multiple protection units 31 can be the same or different.

[0104] By arranging the protection unit 31 between the side surface 213 and the housing 1, the side surface 213 has a higher temperature when the battery cell 500 undergoes thermal runaway, which can achieve a better fire extinguishing effect and is not likely to interfere with other components.

[0105] In some embodiments, the multiple side surfaces 213 include two first side surfaces 214 with the largest area and arranged opposite to each other, and at least one protection unit 31 is provided between at least one first side surface 214 and the housing 1.

[0106] Optionally, at least one protection unit 31 is respectively provided between the two first side surfaces 214 and the housing 1.

[0107] The area of the first side surface 214 is the largest and the temperature is higher when thermal runaway occurs. Therefore, by arranging the protection unit 31 between the first side surface 214 and the housing 1, a better fire extinguishing effect can be achieved, and the protection unit 31 can have a larger volume to improve the fire extinguishing ability.

[0108] In some embodiments, at least one protection unit 31 is respectively provided between each side surface 213 and the housing 1.

[0109] The number of protection units 31 provided between different side surfaces 213 and the housing 1 in this embodiment can be the same or different.

[0110] The multiple protection units 31 between each side surface 213 and the housing 1 in this embodiment can be connected together or not connected.

[0111] A protection unit 31 is provided between each side surface 213 and the housing 1, so that when a thermal runaway occurs in the battery cell 500, the protection assembly 3 can extinguish the fire on each side surface 213, further improving the fire extinguishing ability of the protection assembly 3.

[0112] In some embodiments, at least one protection unit 31 is respectively provided between at least two side surfaces 213 and the housing 1, and the multiple protection units 31 provided between different side surfaces 213 and the housing 1 are connected.

[0113] Exemplarily, the multiple protection units 31 can be connected by means of integral molding or hot melt connection or indirectly connected by other connecting parts.

[0114] With such an arrangement, the multiple protection units 31 connected together are not only convenient for assembly, but also can position each other, reducing the displacement in the battery cell 500.

[0115] In some embodiments, at least one protection unit 31 is respectively provided between each side surface 213 and the housing 1, and all the protection units 31 located between all the side surfaces 213 and the housing 1 are connected.

[0116] In this embodiment, the number of the protection units 31 provided between different side surfaces 213 and the housing 1 can be the same or different.

[0117] With such an arrangement, all the protection units 31 connected together are not only convenient for the assembly of the battery cell 500, but also the protection assembly 3 can extinguish the fire on all the side surfaces 213.

[0118] Figure 5 This is a schematic diagram of the protection assembly in the deployed state in the battery cell provided in some embodiments of the present application.

[0119] Please refer to Figure 5 , in some embodiments, the multiple side surfaces 213 include two first side surfaces 214 with the largest area and arranged back to back, the protection assembly 3 further includes a connecting portion 32, the connecting portion 32 faces the bottom surface, and at least two protection units 31 facing the two first side surfaces 214 are connected by the connecting portion 32.

[0120] The connecting portion 32 in this embodiment can be a strip structure or a plate structure, etc. Optionally, the connecting portion 32 is provided with through holes for infiltrating the electrolyte or for positioning the protection assembly 3.

[0121] The protection unit 31 in this embodiment can be connected to the connecting portion 32 by means of integral molding or hot melt connection, etc.

[0122] A connecting part 32 is provided on the bottom surface to connect at least two protection units 31. Thus, multiple protection units 31 and the connecting part 32 of the protection component 3 are sleeved on the electrode unit 2, which is not only convenient for installation, but also hardly displaces, and plays an insulating role, insulating the electrode unit 2 from the outer shell 1.

[0123] In some embodiments, the connecting part 32 includes the protection unit 31.

[0124] When the connecting part 32 is arranged to include the protection unit 31, when the battery cell 500 undergoes thermal runaway, the protection component 3 can also play a fire extinguishing role on the bottom surface, improving the reliability of the protection component 3.

[0125] In some embodiments, one side of the opposite sides of the protection unit 31 abuts against the electrode unit 2, and the other side abuts against the outer shell 1, and the encapsulation structure 311 is an insulating structure.

[0126] In this embodiment, one side of all the encapsulation structures 311 directly abuts against the electrode unit 2, and the other side directly abuts against the outer shell 1.

[0127] The encapsulation structure 311 of this embodiment is made of an insulating material, for example, it can be thermoplastic polyurethane (TPU) or polyamide (such as PA12), etc.

[0128] With such an arrangement, the protection component 3 directly insulates the electrode unit 2 from the outer shell 1, and there is no need to provide other insulating parts.

[0129] In some embodiments, a protection unit 31 is provided between the bottom surface and the outer shell 1.

[0130] In this embodiment, a protection unit 31 is provided between the bottom surface and the outer shell 1. Among them, a whole protection unit 31 can be provided between the bottom surface and the outer shell 1, or a part of the protection unit 31 can be provided. When a part of the protection unit 31 is provided, the rest of the protection unit 31 is located between the side surface 213 and the outer shell 1.

[0131] Optionally, at least one protection unit 31 is provided between the bottom surface and the outer shell 1.

[0132] A protection unit 31 is provided between the bottom surface and the outer shell 1 to form a fire extinguishing effect on the bottom surface when the battery cell 500 gets out of control, improving the reliability of the protection component 3.

[0133] In some embodiments, the battery cell 500 further includes an insulating film, the insulating film is located in the accommodation space and sleeved on the outside of the electrode unit 2, and the protection component 3 is provided between the insulating film and the electrode unit 2.

[0134] The insulating film in this embodiment can be a mylar film.

[0135] The protection component 3 is disposed between the insulating film and the electrode unit 2. When thermal runaway occurs, the protection component 3 can act on the electrode unit 2 faster, improving the response speed.

[0136] In some embodiments, the melting point of the encapsulation structure 311 is T, and T satisfies: 130°C < T ≤ 180°C.

[0137] Optionally, the value of T can be 135°C, 140°C, 150°C, 160°C, 170°C or 180°C.

[0138] The melting point of the encapsulation structure 311 is set to be greater than 130°C to meet the temperature requirements during normal cycling of the battery cell 500. The melting point of the encapsulation structure 311 is set to be less than or equal to 180°C to melt in time to release the safety agent when thermal runaway occurs in the battery cell 500.

[0139] In some embodiments, T satisfies: 140°C ≤ T ≤ 160°C.

[0140] Optionally, the value of T can be 140°C, 145°C, 150°C, 155°C or 160°C.

[0141] The melting point of the encapsulation structure 311 is set to be greater than 140°C to meet the temperature requirements during normal cycling of the battery cell 500 with a larger capacity. The melting point of the encapsulation structure 311 is set to be less than or equal to 160°C to melt more in time to release the safety agent when thermal runaway occurs in the battery cell 500.

[0142] In some embodiments, the encapsulation structure 311 is a bag-like structure.

[0143] The bag-like structure in this embodiment refers to a soft structure that is prone to deformation. The bag-like structure is not limited to being square as shown in the figure, and can also be circular, pentagonal, hexagonal, etc.

[0144] The encapsulation structure 311 is set as a bag-like structure. Since the bag-like structure is relatively thin, it is easily melted, and the bag-like structure is prone to deformation, which can better adapt to the space inside the housing 1.

[0145] In some embodiments, the safety agent is a solid safety agent, a liquid safety agent, a gaseous safety agent or a safety agent with coexistence of solid and liquid states.

[0146] The safety agent is set to be in multiple states to facilitate selecting a more suitable safety agent for different types of battery cells. [[ID=3,5]]

[0147] An embodiment of the present application also provides a battery device 200, including the above-mentioned battery cell 500.

[0148] An embodiment of the present application further provides an electrical device, including the above-mentioned battery device 200, and the battery device 200 is used to store or provide electrical energy.

[0149] Please refer to Figures 3 - 5 , an embodiment of the present application provides a battery cell 500, which includes a housing 1, an electrode unit 2, and a protection component 3. An accommodation space is formed inside the housing 1. The electrode unit 2 includes at least one electrode component, and the electrode component is arranged in the accommodation space. The protection component 3 is arranged in the accommodation space and is located between the electrode unit 2 and the housing 1. The protection component 3 includes at least one protection unit 31, and the protection unit 31 includes a packaging structure 311 and a safety agent sealed in the packaging structure 311. The protection component 3 is configured such that when the battery cell 500 undergoes thermal runaway, the packaging structure 311 is melted to release the safety agent, and the safety agent is used to inhibit thermal runaway. The electrode unit 2 includes a main body portion 21, and a first tab 22 and a second tab 23 with opposite polarities. The main body portion 21 includes a top surface 211, a bottom surface, and a plurality of side surfaces 213. The plurality of side surfaces 213 are connected between the top surface 211 and the bottom surface. The first tab 22 and the second tab 23 are arranged on the top surface 211, and a protection unit 31 is provided between the side surface 213 and the housing 1. At least one protection unit 31 is respectively provided between each side surface 213 and the housing 1, and all the protection units 31 located between all the side surfaces 213 and the housing 1 are connected. The protection component 3 further includes a connecting portion 32, and the connecting portion 32 faces the bottom surface. The plurality of side surfaces 213 include two first side surfaces 214 with the largest area and arranged opposite to each other, and at least two protection units 31 facing the two first side surfaces 214 are connected through the connecting portion 32. One side of the opposite sides of the protection unit 31 abuts against the electrode unit 2, and the other side abuts against the housing 1. The packaging structure 311 is an insulating structure.

[0150] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments can be combined with each other.

[0151] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features, but these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A battery cell, characterized in that, Comprising: A housing, an accommodation space being formed inside the housing; An electrode unit, including at least one electrode assembly, the electrode assembly being disposed in the accommodation space; A protection assembly, the protection assembly being disposed in the accommodation space and located between the electrode unit and the housing; The protection assembly includes at least one protection unit, the protection unit including a packaging structure and a safety agent sealed in the packaging structure, the protection unit being configured such that when a thermal runaway occurs in the battery cell, the packaging structure is melted to release the safety agent, and the safety agent is used to inhibit thermal runaway; A tab is provided at the top end and / or the bottom end of the electrode unit, the protection assembly covering at least a part of the outer peripheral side of the portion between the top end and the bottom end of the electrode unit, and being configured to release the safety agent to the portion between the top end and the bottom end of the electrode unit.

2. The battery cell according to claim 1, wherein The electrode unit includes a main body portion, a first tab and a second tab with opposite polarities, the main body portion including a top surface, a bottom surface and a plurality of side surfaces, the plurality of side surfaces being connected between the top surface and the bottom surface, and the first tab and the second tab being disposed on the top surface; The protection unit is provided between the side surface and the housing.

3. The battery cell according to claim 2, wherein The plurality of side surfaces include two first side surfaces with the largest area and opposite to each other, and at least one protection unit is provided between at least one of the first side surfaces and the housing.

4. The battery cell according to claim 2, wherein, At least one protection unit is respectively provided between each side surface and the housing.

5. The battery cell according to claim 2, characterized in that, At least two side surfaces and the housing are respectively provided with at least one protection unit, and the plurality of protection units provided between different side surfaces and the housing are connected.

6. The battery cell according to claim 5, characterized in that, At least one protection unit is respectively provided between each side surface and the housing, and all the protection units located between all the side surfaces and the housing are connected.

7. The battery cell according to claim 6, wherein The plurality of side surfaces include two first side surfaces with the largest area and opposite to each other, the protection assembly further includes a connecting portion facing the bottom surface, and at least two protection units facing the two first side surfaces are connected through the connecting portion.

8. The battery cell according to claim 7, characterized in that, The connecting portion includes the protection unit.

9. The battery cell according to claim 7, wherein One side of the two opposite sides of the protection unit abuts against the electrode unit, and the other side abuts against the housing, and the packaging structure is an insulating structure.

10. The battery cell according to claim 2, characterized in that, The protection unit is provided between the bottom surface and the housing.

11. The battery cell according to any one of claims 1 to 8, characterized in that, The battery cell further includes an insulating film, the insulating film being located in the accommodation space and sleeved outside the electrode unit; The protection assembly is provided between the insulating film and the electrode unit.

12. The battery cell according to any one of claims 1 to 10, characterized in that, The melting point of the packaging structure is T, and T satisfies: 130°C < T ≤ 180°C.

13. The battery cell according to claim 12, characterized in that, T satisfies: 140°C ≤ T ≤ 160°C.

14. The battery cell according to any one of claims 1 to 10, characterized in that, The packaging structure is a bag-like structure.

15. The battery cell according to any one of claims 1 to 10, characterized in that, The safety agent is a solid safety agent, a liquid safety agent, a gaseous fire extinguishing agent or a safety agent with coexistence of solid and liquid states.

16. A battery device, characterized in that, Including the battery cell according to any one of claims 1-15.

17. An electrical device, characterized in that, Including the battery device according to claim 16, the battery device being used for storing or providing electric energy.

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